Water → (S)-1-phenyl-1-(tert-butoxycarbonylamino)-2-(1-trifluoroacetylindoline-5-sulfonyl)aminoethane

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Reaction Conditions

Reaction Steps

A mixture of (S)-2-phenyl-2-tert-butoxycarbonylaminoethylazide (10.50 g, 0.04 mol) dissolved in 250 mL dichloromethane and 2.5 g of 10% Pd/C was hydrogenated for 5 hrs at 70 psi of H2. The catalyst was separated by filtration. To the filtrate triethylamine (8 mL) was added, the mixture was cooled to −20° C. followed by slow addition of 1-(trifluoroacetyl)indoline-5-sulfonyl chloride (12.56 g, 0.04 mol) dissolved in 150 mL dichloromethane. The reaction mixture was then stirred overnight at room temperature. Water (500 mL) was added and the mixture was shaken well, organic layer was separated, shaken with 200 mL 2% citric acid, separated and dried with MgSO4. The drying agent was separated by filtration. The filtrate was concentrated and the title product was precipitated by addition of hexane. Yield: 17.67 g, (86%); (MH)+=514; 1H NMR (DMSO-d6): 1.33 (s, 9H), 2.85-2.99 (m, 2H), 3.26-3.30 (t, J=8.0 Hz, 2H), 4.31-4.35 (t, J=8.0 Hz, 2H), 4.53-4.59 (m, 1H), 7.19-7.35 (m, 6H), 7.66-7.68 (m, 2H), 7.72-7.75 (t, J=6.0 Hz, 1H), 8.13-8.15 (d, J=8.8 Hz, 1H).

Provenance & Evidence